Milling-cutter.



H. LINDLEY MILLING GUTTER.

APPLIOATION FILED DB0. 7, 1908.

Patented Mar. 29, 1910.

CIK

fr i i vri HERBERT LINBLE", OF ALTRNCHAM, ENGLAND.

ll'lLLNG-CUTTER.

To all wzfoml it may concern:

Be it known that l, Herinner Luzerner, a suliiject ot Great Britain,residing at ltrincham, in the county of Chester, Kingdom or GreatBritain, have invented new and useful Improvements in liilling-Cutters,of which the following is a specilication.

My invei'ition relates to improvements in that class of rotary millingcutters for shaping or'cutting metal and other material wherein thecutting edges are formed on loose or separate cutters which are securedin a suitable body by wedges and which can thus be renewed when wornwithout the eX- pense of providing` a new body. in practice it has beeni'ound that this class ot' milling cutters is very expensive to makeowing to the great many cutting blades, blade holes and wedges requiredin coiny oarison to the cuttine surrace obtained and which holes alsoweaken the body ot the cutter, so that hitherto to produce a longcutter, the cutter body had to be made in sections.

My invention has tor its object to provide .means whereby the saiddetects are overcome, that is to say, whereby with a less number ofblades a greater cutting surface can be obtained without weakening thecutter body and such loose cuttii'ig blades are more conveniently andsecurely held in the body and the cutter can be produced at a great dealless cost than hitherto has been the case.

l attain these Objects by the means illustrated in the accompanyingdrawings, in which- Figure l is an end view oartly in section, Figs. 2and 3 longitudinal sections et Fig. l on lines A-A and B-B respectively,Figs. et, 5 and 6 plans detached, and Fig. T an elevation oit a completecutter construct ed in accordance with my invention.

Similar letters refer to similar throughout the several views.

ln carrying out my invention a is the body of the cutter, which isusually oit cylindrical torni and has either a shank o or is bored outand keyed to a separate mandrel whereby it receives motion trom thespindle of the machine. rlhis cutter body is made ot any suitablematerial, preferably steel, and has formed therein a number ot recessesc ot rectangular cre-ss section and semi-circular or approximatelysemi-circular profile, see more particularly 3 parts Specification ofLetters Patent.

Application filed December 1998.

and fl, which recesses can be conveniently and econ omieally cut ormilled out by means oit' a. small circular saw or milling cutter ot asuitable width which is sunlr into the body et the cutter a. convenientdepth. The said recesses are disposed around the periphery ot the cutterbody in any convenient manner, the one l generally prefer to adopt isthe tollowingz'llhe recesses which have a length on the surface oit thebody much greater than their width, are arranged so that the longersides lie approximately along a spiral around the body of the cut--ter,y as shown in Fig. 7, several such spiral rows ot recesses beingtermed according to the size ot and milled radially or approxi.- materadially' in the body olf the cutter. in each ol these recesses isfitted a. loose blade Z ot steel ot a. quality suitable for cuttingtools and having a semi-circular prolile corresponding to the shape otthe recesses in the body ot the cutter and projecting a suitabledistance beyond the sur tace et saine so to leave room ior cuttings andallow for s r ,rpening and wear.

in order to securely tix the cutting blades Z in the recesses c l employwedges c consisting et short cylinders ot.' steel. each having a flattace milled or formed thereon at a small angle with the axis ot thecutter body. Cylindrical holes j into which the above wedges can slideare drilled in the body of the cutter, one tor each recess and so placedin relation to the recesses that when the cylindrical wedges are placedin the recesses the tlatfaces on same will lie centrally and lairagainst the faces of the cutting` blades, that is, the holes are drilledat an angle with the faces ot the recesses and at such a distancetherefrom that the flat faces on the wedges can be made to securely lit;the blades in position when the wedges are driven home. rlhe tace of thecutter blade l against which the wedge bears can be longitudinallyserrated, as

shown in Fig. 5, so as to indent the wedge c, or the wedge can be madeto enter a groove f/ in the tace of the blade, as shown in F ig. 6, toinsure that the blades shall not rotate in their grooves, but this isnot usually necessary. The projecting portions ot the said cuttingblades are then ground as an ordinary spiral milling cutter.

ln ordinary solid milling cutters the eli'fect of spiral cutting edgeswhen cutting, is to cause a considerable endwise thrust,

especially in long cutters, the direction of such thrust depending onthe hand of the spiral. In cutters constructed according to my inventionhowever, it is possible to set the blades or cutting tools Ztangent-ially to two spirals, as shown in Fig. 7 namely, one left handedfor one half of the length of the cutter body and the other right handedfor the other half, so that the endwise thrust due to one spiral isneutralized by the thrust due to the other.

In order to provide means for extracting the cutting blades when theyrequire renewing, I may if an odd number of spirals are employed, drillholes 7L right through the body of the cutter as shown in Figs. l and 2,which meet the holes in which slide the wedges e. A drift can then beemployed for the purpose of driving the wedges out. In some caseshowever I form a hole in the center of the cutter body, co-aXial withsame and of such a diameter that the wedge holes f can be convenientlydrilled right through to meet the central hole and a driftingarrangement operated in any convenient manner can be employed thereinfor driving out the wedges but such does not form part of my invention.

I claim:

l. In a milling cutter of the type hereinbefore referred to, recessesrectangular in plan and cross section and of semi-circular profileformed in rows in the periphery of the cutter body7 cutting bladeshaving a straight cutting edge and a semi-circular back edge fitting thesaid recesses, the said blades being supported by the said recesses inevery direction and means for securing the said blades in the saidrecesses, all substantially as and for the purpose set forth.

2. In a milling cutter of the type hereinbefore referred to, recesses inthe periphery of the cutter body rectangular in plan and cross sectionand of semi-circular profile cutting blades corresponding in crosssection and profile with the said recesses and means for securing thesaid blades in the said recesses. comprising a cylindrical hole in theperiphery of the cutter body at the side of each of the said blades anda cylindrical wedge in each of the said holes having a flat tapersurface bearing against the exposed side of the cutter blade, allsubstantially as and for the purpose set forth.

3. In a milling cutter of the type hereinbefore referred to, recesses inthe periphery of the critter body rectangular in plan and cross sectionand of circular profile disposed to form two sets of spirals one lefthanded for the one half and the other right handed for the other half ofthe length of the cutter body and cutting blades corresponding in crosssection and profile with and secured in the said recesses, all combinedsubstantially as and for the purpose set forth.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

HERBERT LINDLEY.

Witnesses:

ALFRED BONHARDT, STANLEY E. BRAMALL.

